Existing tiles are not automatically a suitable base for a new floor. Before choosing a levelling product, ask the installer to assess the whole background and the proposed finish. The decision should connect floor condition with finished levels, thresholds and product instructions.
Identify the existing floor
Record the room, approximate area, tile finish and any available information about the construction below it. Note loose areas, cracking, movement or moisture history. If the background is unknown, say so in the quotation brief. Do not describe it as a sound floor.
An installer may need further investigation or testing before deciding what can remain. A photograph and a product shopping list do not establish suitability. Record which checks are needed and who will provide the results.
Choose the intended finish before fixing the preparation scope
The proposed floor covering affects the preparation requirements. Give the installer the exact product reference and installation information, including relevant requirements where underfloor heating is present. Ask for a compatible preparation proposal for that background and covering.
ARDEX’s guidance distinguishes different preparations and products for existing tiled surfaces. Its flooring guidance also makes selection dependent on the project and substrate conditions. That points to a product-specific assessment. There is no universal primer, depth or drying time.
Check the finished level at every junction
Draw the rooms and adjoining surfaces. Record which doors, thresholds, appliances and skirting are retained. Ask how the full proposed build-up affects each junction. A floor that looks acceptable in one room may create an awkward step or prevent an appliance from being removed.
Separate approximate enquiry measurements from the installer’s final setting-out information. If adjoining levels have not been checked, record that as an open item before ordering the finish or releasing door alterations.
Retain-or-remove floor record
| Record | What to confirm |
|---|---|
| Existing condition | Room, construction information, photographs and defects to assess. |
| Assessment | Investigation/test reference, outcome and unresolved questions. |
| Proposed system | Covering and preparation product references; responsible installer. |
| Junctions and release | Finished levels, doors, thresholds, appliances and authorisation to proceed. |
Compare retaining with removing
A useful comparison includes assessment, preparation, disposal, the selected levelling approach and any associated repairs. Removal can expose further work; retaining can leave background risks that must be understood. The cheaper headline option is not necessarily the same finished scope.
Ask how concealed defects discovered during preparation would be reported and agreed. Identify who authorises additional work and whether a provisional allowance has been included. Do not treat an allowance as proof of the condition below the tiles.
Keep a short floor record
Use the record above for each room and attach photographs, product details and test or assessment references. Give unresolved items an owner. The aim is an installation brief people can follow. Your notes are not a technical floor specification.
For a flooring enquiry, send the postcode, room plan, known floor history and chosen covering. Explain retained doors, appliances and adjoining levels. We can discuss the floor-fitting package and preparation responsibilities after the relevant assessment.
Useful next steps
Sources and product information
Have a project in London or the surrounding areas? Send us your project brief, with photographs and the decisions you have already made.